Electric motors are typically rigidly mounted in small appliances such as, for example, vacuum cleaners. This type of rigid mounting, however, can enable vibrations caused by the rotation of the motor to be transmitted to structural components of the appliance resulting in the generation of undesirable noise. In addition, such vibration can loosen screws and result in structural fatigue or separation of components in the appliance.
The use of rubber or rubber-like bushings to isolate vibrations caused by electric motors in appliances is known in the art. Each of Berfield, U.S. Pat. No. 4,586,214, Berfield et al., U.S. Pat. No. 4,642,841 and Berfield, U.S. Pat. No. 4,547,927 discloses the use of a bushing which surrounds a cylindrical boss which extends from an end bell of an electric motor. A longitudinal bore in the boss receives a screw which rigidly attaches the end bell to a mounting plate in the appliance. Because of this rigid attachment, vibrations of the motor are not isolated from the mounting plate, and thus from the appliance as a whole.
It is also known in the art to isolate vibrations emanating from an assembly which includes a motor and a fan impeller in a vacuum cleaner using a mounting means fabricated of rubber or another suitably resilient material. For example, Berfield, U.S. Pat. No. 4,512,713 discloses a vacuum cleaner having rubber-like gaskets disposed above and below a housing in which an impeller is contained.